tufts pharmacology review (1)

8/13/2019 Tufts Pharmacology Review (1)

1/49


2/49

2

b. Lungs

c. Plasma

d. Muscles

e. Kidneys

(c) procaine is an ester; esters are metabolized predominatelyby pseudocholinesterases in the plasma.

10. Which of the following is local anesthetic subject to inactivation by

plasma esterases?

a. Lidocaine

b. Prilocaine

c. Tetracaine

d. Mepivacaine

e. Bupivacaine

(c) esters are metabolized by plasma esterases - tetracaine isthe only ester listed, all the rest are amides

11. The activity of procaine is terminated by

a. Elimination by the kidney

b. Storage in adipose tissuec. Metabolism in the liver only

d. Metabolism in the liver and by pseudocholinesterase in the

plasma

(d) remember #9 above? see the word "mainly"? samequestion, but worded a little differently to throw you off. Again,procaine is an ester; esters are metabolized predominately bypseudocholinesterases in the plasma, but also to some extentby esters in the liver.

12. All of the following factors are significant determinants of the duration

of conduction block with amide-type local anesthetics EXCEPT the

a. pH of tissues in the area of injection

b. Degree of vasodilatation caused by the local anestheticc. Blood plasma cholinesterase levels

d. Blood flow through the area of conduction block

e. Concentration of the injected anesthetic solution

(c) the word "EXCEPT" should alert you that this is basically atrue-false type question with 4 true statements and 1 falsestatement; you just have to figure out which one! In this case,you just have to remember that plasma cholinesterase levelsare only important for the duration of action of ester-type LAs,not amides, which are metabolized in the liver. All the otherstatements are variables which affect duration of the block, butapply to both esters and amides.

13. Which of the following is contraindicated for a patient who had an

allergic reaction to procaine six months ago?a. Nerve block with lidocaine

b. Topical application of lidocaine

c. Topical application of tetracaine

d. Infiltration with an antihistamine

(c) again, just another question that requires you to be able topick out an ester or an amide from a list. Since procaine is anester, only another ester LA would be cross-allergenic. In thislist the only ester listed is tetracaine.

14. Bupivacaine (Marcaine ) has all of the following properties relative to

lidocaine (Xylocaine ) EXCEPT bupivacaine

a. Is more toxic

b. Is an ester-type local anesthetic

c. Has a slower onset of action

d. Has a longer duration of action

(d) According to textbooks, local anesthetics fall into thefollowing classes in terms of duration of action: short: procaine;moderate: prilocaine, mepivacaine, lidocaine; long: bupivacaine,tetracaine, etidocaine. Statements (a), 3, and 4 would be true ifthe question was comparing mepivacaine to bupivacaine, whichare structurally similar; but the comparison is to lidocaine. Theonly difference that applies is duration of action ((d)),bupivacaine is longer. (b) is wrong, both are amides.

15. Amide-type local anesthetics are metabolized in the

a. Serum

b. Liver

c. Spleen

d. Kidney

e. Axoplasm

(b) don't forget: esters in plasma; amides in liver

15. The duration of action of lidocaine would be increased in the presence

of which of the following medications?

a. Prazosin

b. Propranolol

c. Hydrochlorothiazide

d. Lisinopril

e. Digoxin

(b) this is an interaction I tested you on several times now youknow why! Propranolol interacts with lidocaine in two ways.By slowing down the heart via beta receptor blockade, blooddelivery (and lidocaine) to the liver is reduced, thus lidocaineremains in the systemic circulation longer, and can potentiallyaccumulate to toxic levels. Propranolol and lidocaine alsocompete for the same enzyme in the liver, thus metabolism oflidocaine can be reduced.

16. Severe liver disease least affects the biotransformation of which of

the following?

a. Lidocaine

b. Procaine

c. Prilocaine

d. Mepivacaine

(b) Answer is (b)- You should be able to recognize that all ofthese drugs are local anesthetics. Local anesthetics are of oneof two types, either esters or amides. Ester types are subject tohydrolysis in the plasma and thus have short half lives. Amides

are metabolized primarily in the liver and have longer half lives.Thus the biotransformation (e.g., metabolism; again, the rats areusing a different word to confuse you, even though they areasking the same basic question) of an amide type localanesthetic would be the most altered in the presence of severliver disease. The key word here is "least". Of the drugs listed,only procaine is an ester. The rest are amides.

Questions regarding toxicity:

Generated by Foxit PDF Creator Foxit Softwarehttp://www.foxitsoftware.com For evaluation only.


3/49

Prepared by M.L. Thompson, Ph. D., Dept. of General Dentistry, Tufts Dental School

C:\Documents and Settings\mthomp01\Desktop\pharm2007 shortcuts\Boards2005.doc

3

17. A patient has been given a large volume of a certain local anesthetic

solution and subsequently develops cyanosis with

methemoglobinemia. Which of the following drugs most likely was

administered?

a. Procaine

b. Prilocaine

c. Dibucaine

d. Lidocaine

e. Mepivacaine

(b) strictly memorization

18. Use of prilocaine carries the risk of which of the following adverse

effects?

a. Porphyria

b. Renal toxicity

c. Gastric bleeding

d. Methemoglobinemia

(d) same as above but asked backwards. Methemoglobinemiamay result from a toluidine metabolite of prilocaine,orthotoluidine.

19. The most probable cause for a serious toxic reaction to a local

anesthetic is

a. Psychogenic

b. Deterioration of the anesthetic agent

c. Hypersensitivity to the vasoconstrictor

d. Hypersensitivity to the local anesthetic

e. Excessive blood level of the local anesthetic

(e) Most toxic reactions of a serious nature are related toexcessive blood levels arising from inadvertent intravascularinjection. Hypersensitivity reactions (options b & c) are rare, butexcessive blood levels will induce toxic reactions like CNSstimulation in most everyone. This is a case where option (e) isthe "best" answer, because it is more likely than the other

alternatives, which might be true, but are not as likely (e.g,most probable) to happen.

20. High plasma levels of local anesthetics may cause

a. Inhibition of peristalsis

b. stimulation of baroreceptors resulting in severe hypotension

c. Inhibition of the vagus nerve to the heart

d. Depression of inhibitory neurons in the CNS

(d) Initially LAs inhibit central inhibitory neurons, which results inCNS stimulation, which can proceed to convulsions. At higherdoses, they inhibit both inhibitory and excitatory neurons,leading to a generalized state of CNS depression which canresult in respiratory depression and death.

20a. Unfortunately, you injected your lidocaine intra-arterially. The first

sign of lidocaine toxicity that might be seen in the patient would be

a. Elevated pulse rate

b. Sweating

c. CNS excitation

d. Cardiovascular collapse

e. CNS depression

(c) same question as above just worded differently. The intra-arterial injection would result in the high plasma levelsmentioned in the previous question.

20. The first sign that your patient may be experiencing toxicity from too

much epinephrine would be

a. Cardiovascular collapse

b. Convulsions

c. Elevated pulse rate

d. Slurred speech

(c) it is a sympathomimetic after all. All the other reactions arerelated to elevated lidocaine levels

20. Which disease condition would make the patient most sensitive to the

epinephrine in the local anesthetic?

a. Graves disease

b. Diabetes

c. HIV

d. Alcoholisme. Schizophrenia

(a) Graves disease is an autoimmune disease that causeshyperthyroidism the resulting high levels of circulating thyroidhormone result in a hypermetabolic state with heightenedsympathetic activity, which combined with injected epinephrinecould result in a hypertensive crisis.

21. Cardiovascular collapse elicited by a high circulating dose of a local

anesthetic may be caused by

a. Syncope

b. Vagal stimulation

c. Histamine release

d. Myocardial depression

e. Medullary stimulation

(d) Cardiovascular collapse is due to a direct action of the localanesthetic on the heart muscle itself (LA's in toxic dosesdepress membrane excitability and conduction velocity), thus(d) is the correct answer. All of the other alternatives are indirecways to affect the heart.

22. The most serious consequence of systemic local anesthetic toxicity isa. Vertigo

b. Hypertension

c. Hyperventilation

d. Post depressive central nervous system convulsions

e. Postconvulsive central nervous system depression

(e) Of the options listed, this is the one that will kill the patient,which I guess makes it the most serious.

23. Hypotensive shock may result from excessive blood levels of each of

the following local anesthetics EXCEPT

a. Cocaine

b. Procaine

c. Lidocaine

d. Tetracaine

e. Mepivacaine

(a) All the listed local anesthetics except cocaine arevasodilators, especially ester-ctype drugs such as proccaineand the amide lidocaine. Cocaine is the only local anestheticthat predictably produces vasoconstriction. Cocaine is also theonly local anesthetic to block the reuptake of NE into adrenergicneurons, and thus potentiate the NE that has been releasedfrom nerve endings



4/49

4

24. Which of the following anesthetic drugs produces powerful

stimulation of the cerebral cortex?

a. Cocaine

b. Procaine

c. Lidocaine

d. Tetracaine

e. Mepivacaine

(a) see explanation above

Questions regarding mechanism of action:

25. Local anesthetics block nerve conduction by

a. Depolarizing the nerve membrane to neutrality

b. Increasing membrane permeability to K+

c. Increasing membrane permeability to Na+

d. Preventing an increase in membrane permeability to K+

e. Preventing an increase in membrane permeability to Na+

(e) didnt I make you memorize this? You should at keastremember Na+ ions are involved, which limits your choices to

(c) and (e). (c) would increase or facilitate nervous impulseconduction, which is the opposite of what you want the localanesthetic to do, so pick (e).

26. Which of the following is true regarding the mechanism of action of

local anesthetics?

a. Usually maintain the nerve membrane in a state of

hyperpolarization

b. Prevent the generation of a nerve action potential

c. Maintain the nerve membrane in a state of depolarization

d. Prevent increased permeability of the nerve membrane to

potassium ions

e. Interfere with intracellular nerve metabolism

(b) this should be really obvious!

27. Local anesthetic agents prevent the generation of nerve impulses by

a. Decreasing threshold for stimulation

b. Decreasing resting membrane potential

c. Decreasing inward movement of sodium ion

d. Increasing inward movement of potassium ion

(c) Answer is (c)- straight memorization- nerve impulses aregenerated by the influx of sodium resulting in depolarization.repolarization and inactivity occurs when potassium moves out.(sodium-potassium pump). LAs act by blocking Na+ movement.

28. Local anesthetics interfere with the transport of which of the following

ions during drug-receptor interaction

a. Sodium

b. Calcium

c. Chloride

d. Potassium

e. Magnesium

(a) see how many different ways they can ask the samequestion?

Questions regarding pH effects on absorption of local anesthetics

30. If the pH of an area is lower than normal body pH, the membrane

theory of local anesthetic action predicts that the local anesthetic

activity would be

a. Greater, owing to an increase in the free-base form of the drug

b. Greater, owing to an increase in the cationic form of the drug

c. Less, owing to an increase in the free-base form of the drug

d. Less, owing to a decrease in the free-base form of the druge. None of the above

(d) the next three or four questions are all versions of the samething see the explanation below

31. A local anesthetic injected into an inflamed area will NOT give

maximum effects because

a. The pH of inflamed tissue inhibits the release of the free base

b. The drug will not be absorbed as rapidly because of the

decreased blood supply

c. The chemical mediators of inflammation will present a chemical

antagonism to the anesthetic

d. Prostaglandins stabilize the nerve membrane and diminish the

effectiveness of the local anesthetic

(a) while some of the other alternatives sound plausible, thinkabout the factoids you were taught about local anesthetics andvariables that affect their action. An important one was the roleof pH and ionization factors. Remember, the free base ornonionized form is the form that passes through membranes,yet once inside the neuron only the ionized form is effective.Inflamed tissue has a lower pH than normal tissue and will shiftthe equilibrium of the LA solution such that most of it remainsionized and thus unavailable to penetrate

32. The penetration of a local anesthetic into nervous tissue is a function

of the

a. Length of the central alkyl chain

b. Lipid solubility of the ionized form

c. Lipid solubility of the unionized formd. Ester linkage between the aromatic nucleus and the alkyl chain

e. Amide linkage between the aromatic nucleus and the alkyl chain

(c) only options (b) and (c) are relevant here - the others havenothing to do with LA penetration into membranes. Membranepermeability is affected by whether or not the molecule ischarged or ionized or not (e.g., unionized). Only the latter formpasses readily through membranes. See, theyre asking thesame thing they asked in the previous question, just coming at ifrom another angle. Remember the fact and you can cover theangles.

35. At a pH of 7.8, lidocaine (pKa = 7.8) will exist in

a. the ionized form

b. the nonionized formc. an equal mixture of ionized and nonionized forms

d. a mixture 10 times more ionized than nonionized forms

(c) the ratio of ionized to unionized forms is given by theformula log A/AH= pH-pKa. In this instance the differencebetween pH and pKa is 0. Thus lidocaine will exist as an equalmixture ( so (c) is correct). Most local anesthetics are weakbases with pKa ranging from 7.5 to 9.5. LAs intended forinjection are usually prepared in salt form by addition of HCl.They penetrate as the unionized form into the neuron wherethey re-equilibrate to both charged and uncharged forms inside



5/49



5

the neuron - the positively charged ion blocks nerve conduction.

33. The more rapid onset of action of local anesthetics in small nerves is

due to

a. The slightly lower pH of small nervesb. The greater surface-volume ratio of small nerves

c. The increased rate of penetration resulting from depolarization

d. Smaller nerves usually having a higher threshold

Who knows? Who cares? probably the answer is (b) - the theorygoes that there is a size dependent critical length ofanesthetic exposure necessary to block a given nerve. Smallfibers will be blocked first because the anestheticconcentration to h critical length in a small fiber will be reachedfaster than the critical length in a larger fiber. You have toblock three nodes of ranvier, and they are farther apart inlarger fibers than they are in small diameter fibers. Makesense?

34. Which of the following statements are true regarding onset, degree

and duration of action of local anesthetics?

a. The greater the drug concentration, the faster the onset and thegreater the degree of effect

b. Local anesthetics block only myelinated nerve fibers at the nodes

of Ranvier

c. The larger the diameter of the nerve fiber, the faster the onset of

effectd. The faster the penetrance of the drug, the faster the onset of

effect

i. (a), (b), and (c)

ii. (a), (b) and (d)

iii. (a) and (c) only

iv. (b), (c) and (d)

(ii) if you knew the fact above about small nerves, then thisquestion basically becomes a true false type thing, and (c) is the

false statement. (a) and (d) make logical sense so you arestuck picking between (b) and (c). You have your pick ofmemorizing the small nerve thing or the myelinated nerve nodesof ranvier thing.

And now, for those of you that complained in class do we really

have to know this stuff?

35. A dentist administers 1.8 ml of a 2% solution of lidocaine. How many

mg of lidocaine did the patient receive?

a. 3.6

b. 9

c. 18

d. 36e. 180

(d) 2% solution = 20 mg/ml X 1.8 ml = 36 mg lidocaine. Andyou thought you would never have to do this stuff again!

36. Three ml of a local anesthetic solution consisting of 2% lidocaine with

1:100,000 epinephrine contains how many milligrams of each?

a. 6 mg. lidocaine, 0.3 mg. epinephrine

b. 6 mg. lidocaine, 0.03 mg. epinephrine

c. 60 mg. lidocaine 0.3 mg. epinephrine

d. 60 mg. lidocaine 0.03 mg epinephrine

e. 600 mg lidocaine, 0.3 mg. epinephrine

f. 600 mg. lidocaine, 0.03 mg. epinephrine

(d) 2% lidocaine = 20 mg/ml x 3 = 60 mg lidocaine1:100,000 epi = 0.01 mg/ml x 3 = 0.03 mg epi

37. The maximum allowable adult dose of mepivacaine is 300 mg. How

many milliliters of 2% mepivacaine should be injected to attain themaximal dosage in an adult patient?

a. 5

b. 10

c. 15

d. 20

e. 25

(c) 2% mepivacaine = 20 mg/ml, so 300 mg / 20 mg/ml = 15 ml

38. A recently introduced local anesthetic agent is claimed by the

manufacturer to be several times as potent as procaine. The product

is available in 0.05% buffered aqueous solution in 1.8 ml. cartridge.

The maximum amount recommended for dental anesthesia over a 4-

hour period is 30 mg. The amount is contained in approximately how

many cartridges?a. 1-9

b. 10-18

c. 19-27

d. 28-36

e. Greater than 36

(d) 0.05% = 0.5 mg/ml . To give 30 mg, you have to give30mg/0.5 mg/ml or 60 ml. 1 cartridge = 1.8 ml, thus 60ml /1.8ml= 33.3 cartridges. - first express the percentage of solution as afraction of 100, then add the units gm/ml. 0.05% equals 0.5 or1/2 gms per 100 ml. The cartridge is 1.8 ml which you canround off to almost 2 mls total. In this 2 ml you would have 1 gmof the local anesthetic. You need to give 30 gms, which wouldrequire 30 cartridges. The alternative that meets this answer is(d). Don't get tricked by the placement of the decimal point-

many people read the 0.05% as being the same as 5 gmsrather than 0.5 gms.

39. According to AHA guidelines, the maximum # of carpules of

local anesthetic containing 1:200,000 epinephrine that can be used

in the patient with cardiovascular disease is

a. 1

b. 2

c. 3

d. 4

e. 11

(d) the AHA limit is 0.04 mg, compared to 0.2 mg in the healthypatient. 1:200,000 equals 0.005 mg/ml or 0.009 per 1.8 mlcarpule. 4 carpules would thus contain 0.036 mg, which is just

below the 0.04 mg limit

Antibiotics

1. The most frequently asked type of question requires you to be able to

compare various penicillin antibiotics in terms of potency against

certain bugs, allergenicity, drug of choice against certain conditions,

etc. For example:



6/49


7/49



7

hepatitis

4. Questions involving interactions between antibiotics and other drugs:

a. Tetracycline and penicillin (cidal-static interaction)cancel each

other out due to opposing mechanisms of action

b. Probenecid alters the rate of renal clearance of penicillin

c. Effectiveness of tetracyclines is reduced by concurrent

ingestion of antacids or dairy products

d. Broad spectrum antibiotics enhance the action of coumarin

anticoagulants because of the reduction of Vitamin K sources

e. Antibiotics such as ampicillin decrease the effectiveness of

oral contraceptives due to suppression of normal Gl florainvolved in the recycling of active steroids from bile conjugates,

leading to more rapid excretion of the steroids from the body

f. Macrolides such as erythromycin inhit the metabolism of drugs

such as seldane, digoxin, etc.

5. More and more questions these days are being asked about

antivirals and antifungals, so review

a. Acyclovir: an antiviral used for various forms of herpes

b. Fluconazole or ketoconazole: systemic-acting antifungals

useful for treating candidiasis

Frequently asked questions on antibiotics:

5. For treating most oral infections, penicillin V is preferred to penicillin G

because penicillin V

a. Is less allergenic

b. Is less sensitive to acid degradation

c. Has a greater gram-negative spectrum

d. Has a longer duration of action

e. Is bactericidal, whereas penicillin G is not

(b) memorization: basically the only difference

6. The sole therapeutic advantage of penicillin V over penicillin G is

a. Greater resistance to penicillinase

b. Broader antibacterial spectrum

c. More reliable oral absorption

d. Slower renal excretion

e. None of the above

(c) reworded version of the above

7. Which of the following penicillins is administered ONLY by deep

intramuscular injection?a. Ampicillin

b. Dicloxacillin sodium

c. Penicillin G procaine

d. Penicillin V potassium

(c) Answer is (c)- (a), (b) and (d) are all used orally. Penicillin Gis destroyed by acid in the stomach resulting in variable andirregular absorption. Penicillin V is acid stable and available fororal use. Penicillin G procaine is typically given intramuscularlyin repository form, yielding a tissue depot from which the drug isabsorbed over hours. In this form, it cannot be given IV orsubcutaneously.

8 The principal difference among potassium, procaine and benzathine

salts of penicillin G is theira. Potency

b. Toxicity

c. Duration of action

d. Antibacterial spectrum

e. Diffusion into the cerebrospinal fluid

(c) again, just asking you to know something about the variousforms of penicillin. Since in most cases you are going to use PenVK orally, this question is an old one showing its age and probablynot likely to appear anymore on board excams

11. Which of the following antibiotics is cross-allergenic with penicillin

and should NOT be administered to the penicillin-sensitive patient?

a. Ampicillin

b. Erythromycin

c. Clindamycin

d. Lincomycin

e. Tetracycline

(a) ampicillin sort of sounds like penicillin so it must be theanswer

12. Which of the following antibiotics may be cross-allergenic with

penicillin?

a. Neomycin

b. Cephalexin

c. Clindamycin

d. Erythromycin

e. All of the above

(b) This is a memorization question, with (b) the correctanswer. You have to remember that the cephalosporins (likecephalexin) are chemically related to the penicillins. The othersare not chemically related and thus cross-allergenicity is unlikely

13. Which of the following antibiotics shows an incidence of

approximately 8% cross-allergenicity with penicillins?

a. neomycin

b. cephalexin

c. bacitracin

d. vancomycin

e. tetracycline

(b) just slightly reworded version of the above question, but withsome different alternatives thrown in. Obviously, if you canrecognize whther or not a drug is a penicillin or a cephalosporin ,and you remember that these are the classes that show cross-allergenicity, then you can handle any rewording of this question.

14. Which of the following groups of antibiotics is related both structurallyand by mode of action to the penicillins?

a. Polymyxins

b. Cycloserines

c. Cephalosporins

d. Chloramphenicols

(c) see above

13. For the dentist, the most reliable method of detecting a patient's

allergy to penicillin is by



8/49

8

a. Injecting penicillin intradermally

b. Taking a thorough medical history

c. Placing a drop of penicillin on the eye

d. Having the patient inhale a penicillin aerosol

e. Injecting a small amount of penicillin intravenously

(b) all of the other methods involve unacceptable risk. Oncesensitized, even a small amount can cause an allergic

response. Remember, it is not a dose-related response thatwont be problematic if you only inject a little bit.

14. Which of the following antibiotics is the substitute of choice for

penicillin in the penicillin-sensitive patient?

a. Bacitracin

b. Erythromycin

c. Tetracycline

d. Chloramphenicol

(b) boy, if you havent heard this a zillion times by now.. None ofthe alternatives listed would be a problem in terms of cross-allergenicity, but the reason (b) is the right answer is that thespectrum of activity of erthromycin is very similar to penicillin. Theothers offer a much broader spectrum of coverage than we usually

require; always use the drug with the narrowest spectrum possiblethat includes the microbe in question. Standards have nowchanged such that clindamycin is the drug of choice in this

situation. But if they dont include clindamycin, look for

erythromycin, or for that matter Azithromycin

15. Most anaphylactic reactions to penicillin occur

a. When the drug is administered orally

b. In patients who have already experienced an allergic reaction tothe drug

c. In patients with a negative skin test to penicillin allergy

d. When the drug is administered parenterally

e. Within minutes after drug administration

i. (a), (b) and (d)

ii. (b), (c) and (d)iii. (b), (d) and (e)

iv. (b) and (e) only

v. (c), (d) and (e)

(iii) memorize

16. Which of the following penicillins has a broader gram-negative

spectrum than penicillin G?

a. Nafcillin

b. Ampicillin

c. Cephalexin

d. Methicillin

e. Penicillin V

(b) thats why it is considered an extended-spectrum form ofpenicillin

17. Which of the following penicillins has the best gram-negative

spectrum?

a. Nafcillin

b. Ampicillin

c. Methicillin

d. Penicillin V

e. Phenethicillin

(b) didnt they just ask the same thing in the question above?

18. Which of the following antibiotics should be considered the drug of

choice in the treatment of infection caused by a penicillinase-

producing staphylococcus?

a. Neomycin

b. Ampicillin

c. Tetracyclined. Penicillin V

e. Dicloxacillin

(e) thats really the only use for dicloxacillin

19. Oral infections caused by organisms that produce penicillinase

should be treated with

a. Ampicillin

b. Dicloxacillin

c. Erythromycin

d. Any of the above

e. Only (a) or (c) above

(b) of those listed only (b) is penicillinase resistant. Ampicillin is an

extended spectrum penicillin, and is not penicillinase resistant.Erythromycin shouldnt be affected by penicillinases, since it isnt apeniciilin, but it doesnt work against staph for other reasons.

20. Which of the following antibiotics is LEAST effective against

penicillinase-producing microorganisms?a. Ampicillin

b. Cephalexin

c. Methicillin

d. Clindamycin

e. Erythromycin

(a) same question asked backassward

21. Which of the following is a bactericidal antibiotic used specifically in

the treatment of infections caused by Pseudomonasspecies andindole-positive Proteusspecies?

a. Ampicillin

b. Penicillin V

c. Tetracycline

d. Dicloxacillin

e. Carbenicillin

(e) Wow, I bet you didnt think they would ask something likethis!. An extended spectrum agent is required. Ampicillin isineffective, while Pen-V is too narrow in spectrum.

22. Penicillin's effectiveness against rapidly growing cells is primarily due

to its effect on

a. Protein synthesis

b. Cell wall synthesisc. Nucleic acid synthesis

d. Chelation of metal ions

e. Cell membrane permeability

(b) memorize, memorize

23. Chlortetracycline acts by interfering with

a. Cell wall synthesis

b. Nuclear acid synthesis

c. Protein synthesis on bacterial but not mammalian ribosomes



9/49



9

d. Protein synthesis on mammalian but not bacterial ribosomes

(c) thats why it is selectively toxic. Wouldnt you like it if yourdoctor prescribed a drug for you that did (d)?

24. The probable mechanism of the bacteriostatic action of sulfonamides

involves

a. Disruption of the cell membraneb. Coagulation of intracellular proteins

c. Reduction in oxygen utilization by the cells

d. Inhibition of metabolism by binding acetyl groups

e. Competition with para-aminobenzoic acid in folic acid synthesis

(e) memorize

25. The sulfonamides act by

a. Suppressing bacterial protein synthesis

b. Inhibiting the formation of the cytoplasmic bacterial membrane

c. Inducing the formation of "lethal" bacterial proteins

d. Inducing a deficiency of folic acid by competition with para-

aminobenzoic acid

(d) same as above worded differently

26. Which antibiotic is able to achieve a higher concentration in bone

than in serum?

a. penicillin

b. erythromycin

c. clindamycin

d. metronidazole

e. amoxicillin

(c) thats why it is very useful for treating bone infections suchas osteomyelitis. The question might have substituted gingivalfluid for bone that would make the answer tetracycline

27. Tetracycline reduces the effectiveness of concomitantly administered

penicillin bya. Reducing absorption of penicillin

b. Increasing metabolism of penicillin

c. Increasing renal excretion of penicillin

d. Increasing binding of penicillin to serum proteins


(e) tetracycline is bacteriostatic and would slow the rapidgrowth of the microbial population that a bactericidal drug suchas penicillin needs to be effective, sine only when rapidlydividing are the cells making cell walls

37. The action of which of the following drugs will most likely be impairedby concurrent administration of tetracycline?

a. Clarithromycin

b. Erythromycin

c. Sulfonamided. Penicillin

e. Lincomycin

(d) the classic cidal- static interaction! See above, since this isjust a reworded version of the same fact

28. Which of the following antibiotics is most likely to cause liver

damage?

a. Streptomycin

b. Penicillin G

c. Tetracycline

d. Cephalosporins

e. Amphotericin B

(c) (a) streptomycin can damage the eighth nerve, affectingboth balance and hearing, but is not associated with liverdamage. (b) other than allergic reactions, penicillins areextremely safe, with no effect on the liver. (d) the

cephalosporins are chemically related to the penicillins andshare their relatively nontoxic nature. (e) amphotericin B, is anantifungal agent that produces such adverse side effects asnephrotoxicity and hypokalemia, but not liver toxicity. Thus (c) isthe correct answer. Tetracyclines have been shown to behepatotoxic following high doses in pregnant patients with ahistory of renal disease.

29. Which of the following erythromycins associated with an allergic

cholestatic hepatitis?

a. Erythromycin base

b. Erythromycin stearate

c. Erythromycin estolate

d. Erythromycin succinate

(c) just because

30. Which of the following antibiotics is LEAST likely to cause

superinfection?

a. Gentamicin

b. Tetracyclinec. Penicillin G

d. Streptomycin

e. Chloramphenicol

(c) superinfections are usually seen following the use of broadspectrum agents. Of those listed, all are wide spectrum exceptPen-G

31. Gastrointestinal upset and pseudomembranous colitis has been

prominently associated witha. Nystatin

b. Cephalexin

c. Clindamycin

d. Polymyxin B

e. Erythromycin

(c) The only 2 possibilities that produce GI upset are (c) and(e). As for producing colitis, (b) and (c) are associated with thisadverse side effect. (c) is the only drug which does both,therefore it's the right answer.

32. Symptoms that may be characterized as allergic manifestations

during penicillin therapy are

a. Deafness, dizziness and acute anemia

b. Crystalluria, nausea, vomiting and anaphylactic shockc. Oliguria, hematuria, bronchoconstrict ion and cardiovascular

collapse

d. Dermatitis, stomatitis, bronchoconstriction and cardiovascular

collapse

(d)

33. Aplastic anemia is a serious toxic effect that occurs particularly after

a course of treatment with which of the following antibiotics?

a. Penicillin



10/49

10

b. Lincomycin

c. Tetracycline

d. Streptomycin

e. Chloramphenicol

(e) memorize

34. Each of the following is a side effect of prolonged tetracyclinehydrochloride therapy EXCEPT:

a. Suprainfection

b. Photosensitivity

c. Vestibular disturbances

d. Discoloration of newly forming teeth

e. Gastrointestinal symptoms (when administered orally)

(c) memorize

36. Colitis that results following clindamycin therapy is caused by an

overgrowth of

a. C. dificile

b. Staph aureus

c. Pseudomonasd. Candida albicans

(a) memorize

Antibiotics, Miscellaneous

37. Which antibiotic is appropriate for premedication in the penicillin

allergic patient?

a. Cephalexin

b. Clindamycin

c. Erythromycin

d. Amoxicillin

e. Ampiciilin

(b) clindamycin is the current recommendation. Erythromycinused to be, so if you get a question that doesnt includeclindamycin as an answer, look for erythromycin. Cephalexinmight be a choice, but there is the issue of cross-allergencicity,and it must certainly be avoided in the anaphylactic patient.Amoxicillin and ampicillin are penicillins!

38. Acyclovir is useful for treating

a. Candidiasis

b. Colitis

c. Herpes simplex

d. HIV

e. ANUG

(c) always think used for herpes as the first answer

38. A distinct advantage that tetracyclines have over penicillins is that

tetracyclines

a. Have no side effects

b. Do not cause superinfections

c. Are safer to use during pregnancy

d. Have a wider range of antibacterial activity

e. Produce higher blood levels faster after oral administration

(d) broad spectrum vs . narrow spectrum. Tetracyclines certainlyhave more side effects than penicillin, and are certainly one of

the antibiotics to avoid during pregnancy.

39. Which of the following has the broadest antimicrobial spectrum?

a. Vancomycin (Vancocin )

b. Clindamycin (Cleocin )

c. Erythromycin (Erythrocin )

d. Chlortetracycline (Aureomycin )

e. A third generation cephalosporin

(d) Answer is (d)- remember, tetracyclines are broad spectrumantibiotics effective against both gram-negative and gram-positive cocci and bacilli. Clindamycin has a spectrum of activitysimilar to erthyromycin and vancomycin, which is less than thatof the tetracylines, mainly affecting gram-positivemicroorganisms. Ist generation cephalosporins are effectiveagainst both gram-negative and gram-positive organisms, butthe third generation ones have increased activity against gram-negative but greatly decreased activity against gram-positivemicroorganisms.

40. Sulfonamides and trimethoprim are synergistic bacteriostatic agents

because in bacteria they

a. Both inhibit folic acid synthesisb. Interfere sequentially with folinic acid production

c. Are both antimetabolites of para-aminobenzoic

d. Are both inhibitors of dihydrofolic acid reductase

e. Are both transformed in vivointo a single active compound

(b)

41. Which of the following substances is the most effective agent against

fungus infections of the mucous membrane?

a. Nystatin ointment

b. Undecylenic acid

c. Polymyxin ointment

d. Saturated magnesium sulfate

e. 10 per cent aluminum chloride solution

(a)

42. The most desirable property of an antibiotic when used to treat an

odontogenic infection is

a. Rapid absorption

b. Little allergenicity

c. Ability to achieve and maintain adequate concentrations at the

site of infection

d. Lack of significant binding to plasma proteins

e. No effects on drug metabolism

(c) if it cant do this it isnt going to be very effective.

14. Nystatin is of greatest clinical usefulness in treating

a. viral infections

b. fungal infectionsc. spirochetal infections

d. Bacterroides infections

e. penicillin resistant gram positive infections

(b) Nystatin is the prototypic antifungal agent, thus (b) is themost obvious 1st choice, and eliminates (a). (d) & (e) require anantibiotic, not an antifungal

42. Which of the following drugs chelates with calcium?



11/49



11

a. Erythromycin

b. Polymyxin B

c. Tetracycline

d. Penicillin G

e. Chloramphenicol

(c)

43. Which of the following is NOT characteristic of tetracycline

antibiotics?

a. Absorption is impaired when taken with antacids

b. They predispose to monilial superinfection

c. They form a stable complex with the developing tooth matrix

d. They have a low tendency for sensitization, but a high

therapeutic index

e. They are effective substitutes for penicillin prophylaxis against

infective endocarditis

Answer is (e)- Again, the important phrase in the question isnot(Hey, just Wayne and Garth). Obviously the fact that you willremember about tetracylines is that they can discolor teeth inthe fetus when taken by the mother during pregnancy. But don'tcircle that answer because (a) is also characteristic of

tetracyclines (they are the most likely of all the antibiotics tocause superinfection), and is an annoying side effect in adultsresulting from alteration of the oral, gastric and intestinal flora.The real answer is (e). Tetracyclines are not the drug of choicefor prophylaxis against infective endocarditis. This is due tostreptococcal infection. 15-20% of group A streptococci areresistant to tetracyclines, but none are resistant to penicillin orerythromycin. Recently a non-streptococcal induced subacutebacterial endocarditis has been identified, especially in juvenileperiodontitis patients. The causative bacterium is notsusceptible to penicillin or erythromycin. It may be necessary totreat predisposed patients with tetracycline for a few weeks, andthen follow this with a course of penicillin or erythromycin.Remember that these drugs are antagonistic to each other andthus can't be used concurrently. Penicillin is a bactericidal drugwhich kills or destroys microorganisms by interfering with thesynthesis or function of the cell wall, cell membrane or both.

Thus it is most effective against bacteria that are multiplying.Tetracycline is a bacteriostatic antibiotic that acts by inhibitingthe growth and multiplication of organisms by inhibiting proteinsynthesis by binding reversibly to the 30 S subunit of thebacterial ribosome. When the two types are given together, theireffectiveness is negated or reduced.

Antibiotics, Drug Interactions

44. The concurrent administration of penicillin G and probenecid results

in

a. Increased metabolism of penicillin G.

b. Increased renal excretion of probenecid

c. Decreased renal excretion of penicillin Gd. Decreased bactericidal effect of penicillin G

e. Increased excretion of probenecid in the feces

(c)

71. Interaction between penicillin and probenicid is best described by

which of the following mechanisms?

a. competition at the receptor site

b. acceleration of drug biotransformation

c. alteration in the acid-base balance

d. alteration in the rate of renal clearance

Answer is (d)- penicillin is metabolized in the liver, but it rapidlydisappears from the blood due to rapid clearance by thekidneys. 90% is excreted by tubular secretion. Thus patientswith renal disease will show high blood levels of penicillin.Similarly, probenicid, a uricosuric agent (a drug which tends toenhance the excretion of uric acid by reducing renal tubular

transport mechanisms), reduces the renal clearance ofpenicillins. And you wondered why we had those lectures onpharmacokinetics!

45. When broad-spectrum antibiotics are administered with coumarin

anticoagulants, the anticoagulant action may be

a. Reduced because of enhanced hepatic drug metabolism

b. Reduced because of increased protein-binding

c. Increased because of reduction of vitamin K sources

d. Increased because of decreased renal excretion of the

anticoagulant

(c)

46. The therapeutic effectiveness of which of the following drugs will bemost affected by concomitant ingestion of antacids?

a. Cephalexin

b. Erythromycin

c. Tetracycline

d. Sulfisoxazole

e. Penicillin V

(c) hey, I asked you this on the exam!

47. Erythromycin should be avoided in the patient taking

a. Aspirin

b. Seldane

c. Benadryl

d. Ibuprofen

e. Propranolol

(b) remember the famous erythromycin Seldane potentiallylethal interaction, whereby erythromycin blocks the metabolismof Seldane to its antihistamine metabolite it staysunmetabolized and causes cardiac arrthymias. Of course thisquestion could have many other options listed, sinceerythromycin decreases the metabolism of so many otheruseful drugs, such as digoxin.



12/49

12

Cardiovascular Drugs

This category covers a lot of drugs and a lot of questions. They can

be categorized as:

1. Questions asking about which drug from a list might be used to

treat a certain condition:

hypertension:

1) Diuretics such as the high ceiling or loop-acting diuretic,

furosemide;

2) Beta-blockers such as propranolol or the cardioselective beta

blocker metoprololor atenolol

3) Alpha-1 blockers such as prazosin,

4) Centrally acting adrenergic drugs such as methyldopa or

clonidine

5) Neuronal blockers such as guanethidine (reserved for severe

hypertension)

6) Angiotensin converting enzyme inhibitors such as Captopril,

lisinopril

angina: Nitroglycerin, sometimes propranolol, calcium channel

blockers such as verapamil

arrhythmias:

1) Lidocaine (ventriculararrhythmias),

2) Phenytoin (to reverse digitalis induced arrhythmias),

3) Quinidine (supraventricular tachyarrhythmias, atrial

fibrillation),

4) Verapamil (supraventricular tachyarrhythmias,

paroxysmal tachycardia, atrial fibrillation),

5) Digitalis (atrial fibrillation, paroxysmal tachycardia)

6) Propranolol (paroxysmal tachycardia)

Congestive heart failure:Glycosides such as digitalis, digoxin,

ACE inhibitors such as captopril

2. The second major category of questions concerns mechanism

of action of the various agents:

Antiarrhythmics: Remember problem is that the heart beats

irregularity

a. Type 1A agents such as quinidine: acts by increasing the

refractory period of cardiac muscle

b. Type 1B agents such as lidocaine decrease cardiac

excitability

c. When digitalis is used for atrial fibri llation it acts by

decreasing the rate of A-V conduction

Antiangina drugs: problem is insufficient oxygen to meet demands

of myocardium

a. Nitroglycerin increases oxygen supply to the heart by a direct

vasodilatory action on the smooth muscle in coronary

arteriesb. Propranolol reduces oxygen demand by preventing

chronotropic responses to endogenous epinephrine,

emotions and exercise.

c. Calcium channel blockers decrease oxygen demand by

reducing afterload by reducing peripheral resistance via

vasodilation

Antihypertensives:Remember, most drugs have the ultimate

effect of reducing peripheral resistance via vasodilation

ACE inhibitors: Captopril blocks the enzyme which converts

angiotensin I to angiotensin II. The latter is a potent

vasoconstrictor (administration of angiotensin will result in anelevation of blood pressure).

Adrenergic Agents:

a. Prazosin: selective alpa-1 blocker, inhibits binding of nerve

induced release of NE resulting in vasodilationb. Methyldopa: acts centrally as a false neurotransmitter

stimulating alpha receptors to reduce sympathetic outflow

resulting in vasodilation

c. Clonidine: selective agonist stimulates alpha-2receptors in

the CNS to reduce sympathetic outflow to peripheral vessels

resulting in vasodilation

d. Propranolol: nonselective beta blocker reduces cardiac

output and inhibits renin secretion

e. Metoprolol: selective beta-1 blocker, reduces cardiac output

Diuretics:decrease the renal absorption of sodium, thus resulting

in fluid loss and a reduction in blood volume. This decreases

the work the heart has to pump. Also have weak dilatory

action. Types of diuretics which may be mentioned include:

a. Thiazides: chlorothiazide

b. High-ceiling or loop acting: furosemide

c. Potassium sparing: spironolactone

Congestive heart failure drugs:

a. Cardiac glycosides such as digitalis or digitoxin are

effective because they have a positive inotropic effect,

increasing the force of contraction of the myocardium. This is

achieved by an inhibition of Na+, K+ ATPASE leading to

increased calcium influx. Digitalis therapy reduces the

compensatory changes that are associated with congestive

heart failure such as increased heart size, rate, edema, etc.

Drug-condition questions

1. Quinidine is principally used to treat

a. Hypertension

b. Angina pectoris

c. Congestive hear failure

d. Supraventricular tachyarrhythmias

(d) by elimination. Hypertension ((a)) is treated primarily withbeta blockers such as propranolol. Angina is primarily treatedwith nitroglycerin, while digoxin (digitalis) is the drug of choice forcongestive heart failure. Quinidine is classed as an antiarrthymicdrug (Type I-blocks sodium channels). It reduces automaticityand responsiveness and increases refractoriness. It also has anantimuscarinic action preventing the bradycardia that followsvagal stimulation.

2. Quinidine is used to treat

a. Hypertension

b. Angina pectoris

c. Atrial fibrillation

d. Ventricular fibrillation

e. Congestive hear failure

(c) same question as above, just gave you a different type of



13/49


14/49

14

sinus rhythm of the heart due to disease or injury induceddamage to the impulse conducting systems. They also resultfrom the development of ectopic pacemakers or abnormalpacemaker rhythms. Drugs such as lidocaine are used tonormalize these rhythms. Lidocaine, a local anesthetic,depresses cardiac excitability, answer (b). The refractory periodof cardiac muscle is increased, thus slowing the heart down. Allof the other alternatives given would exacerbate the arrhythmia.

16. When digitalis is used in atrial fibrillation, the therapeutic objective is

to

a. Abolish cardiac decompensation

b. Inhibit vagal impulses to the heart

c. Decrease the rate of A-V conduction

d. Increase the rate of cardiac repolarization

e. Produce a decrease in the rate of atrial contraction

(c)

Antiangina Drugs

17. Nitroglycerin dilates the coronary arteries in angina pectoris by

a. Decreasing the heart rate reflexlyb. Increasing the metabolic work of the myocardium

c. Direct action on smooth muscle in the vessel walls

d. Increasing the effective refractory period in the atrium

e. Blocking beta-adrenergic receptors

(c)

18. Propranolol is of value in treating angina pectoris because it

a. Has a direct action on vascular smooth muscle

b. Blocks autoregulatory mechanisms in the heart

c. Inhibits oxygen metabolism in cardiac cells

d. Provides relief within seconds of an acute anginal attack

e. Prevents chronotropic responses to endogenous epinephrine

emotions and exercise

(e)

ACE Inhibitors

19. Administration of angiotensin results in

a. Anti-inflammatory effects

b. Antihistaminic effects

c. Increased blood pressure

d. Increased heart rate

e. A sedative effect

(c)

20. The primary antihypertensive effect of captopril (Capoten) is due to

accumulation of

a. Serotonin

b. Angiotensin I

c. Angiotensin III

d. Bradykinin metabolites

(b) Captopril is an angiotension-converting enzyme inhibitor thatblocks the activation of angiotension I to angiotension II. Thedecreased blood concentration of angiotension II reduces bloodpressure, because angiotension II is a potent vasoconstrictor.Thus (c) is wrong, accumulation of angiotension I is the usual

effect. Captopril also maintains lowered BP by elevatingbradykinin (which has potent vasodilatory action) in the blood byblocking its metabolism. Thus (d) is wrong, bradykininmetabolites do not accumulate.

21. Administration of angiotensin results in

a. A sedative effectb. Increased heart rate

c. Increased blood pressure

d. Antihistaminic effects

e. Anti-inflammatory effects

(c) I guess because more angiotensin II would be formed, andthat is a potent vasoconstrictor

Mechanism of Action

Diuretics

22. Which of the following is NOT characteristic of the thiazide diuretics?

a. Increase renal excretion of sodium and chloride

b. Increase renal excretion of potassium

c. Increase the toxicity of digitalis

d. Exacerbate existing diabetes

e. Cause hypokalemia

f. Cause hypoglycemia

(f) first off, how can you have an option (f)?! (a) is how diureticslower BP, (b) is why they can cause hypokalemia, which isconveniently option (e), and hypokalemia can potentiate digitalisinduced arrythmias option(c). Theyy apparently can also causehyperglycemia, which would relate to option (d). How the heckare you supposed to remember all of this?

23. The most useful diuretic drugs act by

a. Increasing the glomerular filtration rate

b. Decreasing the renal reabsorption of sodium

c. Decreasing the renal excretion of chlorided. Increasing the renal reabsorption of potassium

e. Increasing the secretion of antidiuretic hormone

(b) people with high BP are always told to reduce salt intake,since high sodium levels cause fluid retention which canincrease BP, so ipso facto, reducing renal reabsorption ofsodium makes BP go down

24. Which of the following drugs act by inhibiting renal reabsorption of

sodium?

a. Urea

b. Chlorothiazide

c. Theophylline

d. digitalis glycosides

e. Procainamide

(b) same question as above, just reversed.

Cardiac Glycosides

25. Digoxin exerts its positive inotropic effect by

a. Activation of adenylcyclase

b. Inhibition of phosphodiesterase

c. An agonist effect of beta-receptors



15/49



15

d. Inhibition of Na+, K+ ATPASE leading to increased calcium

influx

e. Decreasing the amount of calcium available for excitation-

contraction coupling

Answer is (d)- Remember, cardiac glycosides such as digoxinare used in the treatment of congestive heart failure, which isthe failure of the heart to function adequately as a pump and

thus maintain an adequate circulation. Cardiac glycosides arethought to act by altering calcium ion movement, with a desiredeffect of increasing the force of contraction of the myocardium(e.g. the inotropic effect). While several of the alternativesinvolve calcium, the way digoxin does it is via (d), inhibition ofNa+, K+ ATPase, resulting in an increase of calcium ion influxinto the cardiac cells, and a subsequent enhancement of thecontractile mechanism. (a) is the way epinephrine works.

26. Digitoxin is effective in the treatment of cardiac failure because it

a. Is primarily a diuretic

b. Reduces the ventricular rate

c. Decreases abnormal cardiac rhythms

d. Produces peripheral vasoconstriction

e. Has a positive cardiac inotropic action

(e)

27. The primary action of therapeutic doses of digitalis on cardiac muscle

is an increase in

a. Force of contraction

b. Ventricular excitability

c. Refractory period of the atrial muscle

d. Refractory period of the ventricular muscle

e. Rate of conduction of impulse to the muscle

(a)

28. The beneficial effects of digitalis in congestive heart failure result in

part from the fact that digitalis causes

a. A decrease in end-diastolic volumeb. A decrease in end-diastolic pressure

c. An increase in stroke volume and cardiac output

d. A decrease in central venous pressure

e. A decrease in rate of the hear where tachycardia exists

i. (a), (b) and (c)

ii. (a) and (c) only

iii. (c) and (d)

iv. (e) only

v. All of the above

(v)

29. The cardiac glycosides will increase the concentration of which ion in

an active heart muscle?a. Sodium

b. Bromide

c. Calcium

d. Chloride

e. Potassium

(c)

30. Which of the following ions augments the inotropic effect of digitalis?

a. Sodium

b. Lithium

c. Calcium

d. Chloride

e. Magnesium

(c)

31. In the treatment of congestive heart failure, digitalis glycosidesgenerally decrease all of the following EXCEPT

a. Edema

b. Urine flow

c. Heart size

d. Heart rate

e. Residual diastolic volume

(b)

Adrenergic Agents

32. The mechanism of action of prazosin, an antihypertensive agent is to

a. Block beta-adrenergic receptors

b. Inhibit formation of angiotensin IIc. Inhibit nerve-induced release of norepinephrine

d. Stimulate central inhibitory alpha-adrenergic receptors

e. Inhibit the postsynaptic action of norepinephrine on vascular

smooth muscle

(e)

33. Which of the following owes a significant amount of its

antihypertensive effect to a central action?

a. Methyldopa

b. Metoprolol

c. Hydralazine

d. Propranolol

e. Guanethidine

(a) All of these drugs are used to treat hypertension, but act bydifferent mechanisms. (a), methyldopa, is the drug with centralaction- it alters CNS control of blood pressure by acting oncardioregulatory and vasomotor systems of the brain bystimulating alpha2 receptors in the brain stem. Clonidine is theusual drug that is involved in this particular question. (b)metropolol is a selectively blocks beta-1 receptors in the heart toreduce cardiac output. (c) hydralazine has a direct action onvascular smooth muscle to reduce hypertension viavasodilation. (d) propranolol blocks beta receptors in the heart,while (e) guanethidine prevents the release and causesdepletion of catecholamines taken up into storage vesicles andis released like a false transmitter. It does not cross the blood-brain barrier.

34. Which of the following drugs is thought to reduce arterial blood

pressure by activating alpha receptors in the vasomotor center of the

medulla?

a. Prazosin

b. Clonidine

c. Propranolold. Guanethidine

e. Chlorothiazide

(b)- see above explanation



16/49

16

35. Propranolol (Inderal) can be useful in the treatment of hypertension

because it blocks

a. Alpha-1 adrenergic receptors

b. Sodium reabsorption in the kidney

c. The release of renin from juxtaglomerular cells

d. The release of norepinephrine from nerve terminals

e. The reflex tachycardia seen with the use of otherantihypertensives

i. (a) and (b)

ii. (a) and (d)

iii. (b), (c) and (d)

iv. (c), (d) and (e)

v. (c) and (e) only

(v) Answer is (v)- You should immediately recognize thatpropranolol is the prototypic beta-adrenergic receptor blocker,thus any answer with alternative a (i and ii) is wrong. Similarly, dis wrong as well-propranolol is a competitive beta- receptorblocker- it has no effect on NE release. Another drug used forhypertension, Clonidine, acts via this mechanism by stimulatingalpha-2 autoreceptors. Thus ii, iii, and iv are wrong. This leaves

(v) as the only possible right answer. Indeed, aside fromblocking beta-1 receptors, blocking of renin release is thought tobe the other mechanism whereby beta-blockers alterhypertension.

36. One of the proposed mechanisms of the antihypertensive effect of

beta-adrenergic receptor blocking agents is

a. Sedation

b. A diuretic effect

c. An antirenin effect

d. A vagal blocking effect

e. An increase in cardiac output

(c)

37. Selective beta-1 adrenergic agonists will produce which of thefollowing effects?

a. Glycogenolysis

b. Increased cardiac output

c. Decreased diastolic pressure

d. Decreased peripheral resistance

e. Relaxation of bronchial smooth muscle

(b)

Miscellaneous Side Effect Questions

38. Ototoxicity with deafness may encountered occasionally in patients

taking which of the following diuretic agents?

a. Osmotic

b. Thiazidec. Mercurial

d. High-ceiling

(d) answer is (d)- straight memorization- deafness is typicallyassociated with use of ethacrynic acid, a loop or high-ceilingdiuretic. How the hell are you supposed to remember all of thisstuff???

39. Symptoms of digitalis toxicity include all of the following EXCEPT

a. Extrasystoles

b. Nausea and vomiting

c. Yellow-green vision

d. A-V conduction block

e. Decreased P-R interval

(e)

40. Administration of which of the following drugs increases the likelihood

of a toxic response to digitalis?

a. Diazepam

b. Lidocaine

c. Spironolactone

d. Chlorothiazide

e. Acetylsalicylic acid

(d) Chlorthiazide is a diuretic which causes potassium loss orhypokalemia. This results in greater penetration of digitalis intothe myocardium, and thus potential toxicity.

41.



17/49



17

Analgesics- NSAIDS:

1. Mechanism of action questions regarding analgesic, antipyretic and

effects on bleeding:

Analgesic effects: aspirin inhibits the synthesis of prostaglandins

Antipyretic effects: aspirin inhibits PG synthesis in the

hypothalamic temperature regulation center

Bleeding time: inhibit synthesis of thromboxane A2 preventing

platelet synthesis

2. A 2nd type of question has to do with pharmacological or toxic effects

of aspirin: you get to pick which of the list is or is not associated

with aspirin. Therapeutic effects of aspirin include pain relief,

antipyretic effects, antirheumatic and anti-inflammatory effects.

Adverse or toxic effects include all of the following: occult bleeding

from the GI tract, tinnitus, nausea and vomiting, acid-base

disturbance or metabolic acidosis, decreased tubular reabsorption

of uric acid, salicylism, delirium, hyperventilation, etc.

3. A third type of question focuses on the difference between 1) aspirinand acetaminophen, 2) aspirin and other anti-inf lammatories like

prednisone, and 3) between aspirin and ibuprofen:

1) Acetaminophen lacks anti-inflammatory activity, is hepatotoxic,

and does not cause GI upset

2) Anti-inflammatories like prednisone, hydrocortisone,

triamcinolone etc. are steroids and do not act primarily by PG

inhibition

3) Ibuprofen causes much less GI irritation

4) Diflunisal (Dolobid) has a longer half-life than aspirin,

acetaminophen and ibuprofen

4. Newer versions of the boards have questions about COX-2

inhibitors like vioxx. (Which of the following is a COX-2

inhibitor?)

5. These old questions focus a lot on aspirin. Nowadays,

acetaminophen and ibuprofen are used much more

commonly than aspirin, because of the many side effects of

aspirin that turn up in these kinds of questions. So since

aspirin is the comparator prototype drug, reviewing these

questions are still useful.

1) But expect newer questions asking you to know:

a. Acetaminophen causes liver toxicity, especially

when combined with alcohol or taken in excess

of 4 gr/day.

b. Acetaminophen is the drug of choice for the

feverish child (they usually ask the reverse,

which is which drug should be avoided in the

feverish child (aspirin- increased risk of Reyes

syndrome)

Frequently asked questions on NSAIDS

4. The therapeutic effect of the salicylates is explained on the basis of the

ability of the drug to

a. Activate autonomic reflexes

b. Uncouple oxidative phosphorylation

c. Inhibit the synthesis of prostaglandins

d. Competitively antagonize prostaglandins at the receptor site

(c)

5. The mechanism of the antipyretic action of salicylates probably results

from

a. Inhibition of prostaglandin synthesis in the CNS affecting

hypothalamic temperature regulation

b. Inhibition of bradykinin in the periphery leading to sweatingc. Depression of oxidative enzymes leading to decreased heat

production

d. Suppression of cholinergic mediators in the hypothalamus

e. Stimulation of norepinephrine in the hypothalamus

(a)

6. The antipyretic action of salicylates is explained in part by

a. Analgesia leading to sedation

b. Increased blood flow through the hypothalamus

c. Cutaneous vasodilation leading to increased heat loss

d. Depression of oxidative processes leading to decreased heat

production

(c)

7. The locus of action of aspirin's central antipyretic effect is the

a. Brain stem

b. Hypothalamus

c. Basal ganglia

d. Limbic system

e. Cerebral cortex

(b) memorization question- remember antipyresis meansantifever. Temperature regulation center is in the hypothalamus.

8. A patient who has been taking large quantities of aspirin might show

increased postoperative bleeding because aspirin inhibits

a. Synthesis of thromboxane A2 and prevents plateletaggregation

b. Synthesis of prostacyclin and prevents platelet aggregation

c. Synthesis of prostaglandin and prevents production of blood

platelets

d. Thrombin and prevents formation of the fibrin network

e. G.I. absorption of vitamin K and prevents synthesis of blood

clotting factors

(a) The first fact you must remember is that aspirin preventsplatelet aggregation- this limits your choices to (a) and (b). Theyhope to confuse you by using prostacylin, but of course youknow that this is wrong immediately, the right word isprostaglandin, as in (c), but you have already eliminated thatchoice because it doesn't mention prevention of plateletaggregation. Thus, even if you didn't remember that

thromboxane A2 induces platelet aggregation, and aspirinblocks this action, you could get the answer by elimination. (d) ishow heparin works, while (e) is how coumarin works.

9. Anti-inflammatory agents, such as aspirin, interfere with hemostasis b

a. Activating antithrombin

b. Preventing vasoconstriction

c. Inhibiting thrombin generation

d. Inhibiting platelet aggregation

e. Inhibiting polymerization of fibrin



18/49

18

(d)

10. Which of the following anti-inflammatory agents does NOT act

primarily by inhibiting activity of prostaglandin synthetase?

a. Diflunisal

b. Ibuprofen

c. Triamcinolone

d. Oxyphenbutazonee. Acetylsalicylic acid

(c) triamcinolone is a corticosteroid. Corticosteroids inhibitphospholipase A2, the enzymatic step that precedesprostaglandin synthetase. Diflunisal is a salicylate analgesic, likeaspirin.

11. A nonsteroidal, anti-inflammatory agent that appears to produce fewer

gastrointestinal disturbances than high does of aspirin is

a. Ibuprofen

b. Probenecid

c. Pentazocine

d. Acetaminophen

e. Phenylbutazone

(a) you might be tempted to answer acetaminophen, because itdoesnt cause GI upset, but remember it is also not anti-inflammatory. The answer is ibuprofen. Tricky you had to sortthrough two distinguishing characteristics. Good question!

12. Prolonged use of which of the following drugs does NOT cause a

predisposition to gastric irritation and bleeding?

a. Phenytoin

b. Ibuprofen

c. Indomethacin

d. Phenylbutazone

e. Acetylsalicylic acid

(a) This is a straight drug identification question. Answers 2-5are all non-steroidal antiinflammatory drugs which cause gastric

irritation and bleeding due to their effects on prostaglandinsynthesis in the mucosal wall of the gut. # , phenytoin, is ananti-convulsant-its major side effect that often appears as aquestion on boards is the production of gingival hyperplasia.

13. Each of the following agents has been associated with gastricirritation EXCEPT

a. Aspirin

b. Alcohol

c. Ibuprofen

d. Indomethacin

e. Acetaminophen

(e) note the difference in this question and #11 and 12.

Ibuprofen was previously the answer to shows reduced GIirritation, but it does cause some, which you have to rememberto answer #12 and this question. So aspirin and ibuprofen areout. Indomethacin is a very strong NSAID that causes lots of GIirritation, so much that use is limited in humans, so it is out.What about alocohol vs. acetaminophen. Well, you should reallyknow that acetaminophen is usually the answer to these typesof analgesics questions, but if you didnt know that, perhaps youmay know that alcohol also causes GI irritation, so it is out.

14. Which of the following is NOT produced by excessive doses of

acetylsalicylic acid?

a. Delirium

b. Tinnitus

c. Hypothermia

d. Hyperventilation

e. Metabolic acidosis

(c) it only lowers your temperature if you have a fever,, taking

aspirin does not have any effect on body temperature in thenon-feverish patient, but high doses can cause all the othereffects listed.

15. All of the following are pharmacologic and toxicologic properties of

aspirin EXCEPT

a. Tinnitus

b. Analgesia

c. Salicylism

d. Antipyresis

e. Suppression of the immune response

(e)

16. Therapeutic effects of aspirin includea. Analgesiab. Tranquilization

c. Pyretic action

d. Anti-inflammatory action

e. Antirheumatic action

i. (a), (b) and (c)

ii. (a), (c) and (d)

iii. (a), (d) and (e)

iv. (b), (c) and (d)

v. (b), (d) and (e)

(iii)

17. All of the following are pharmacologic or toxicologic properties of

acetylsalicylic acid EXCEPTa. Tinnitus

b. Analgesia

c. Antipyresis

d. Methemoglobinemia

e. Inhibition of prostaglandin synthesis

(d)

18. All of the following are possible effects of aspirin EXCEPT

a. Reduction of fever

b. Shortening of bleeding time

c. Suppression of inflammatory response

d. Bleeding from the gastronintestinal tract

e. Increase in the renal excretion of uric acid at high doses

(e)

19. Of the following, aspirin does NOT cause

a. Occult bleeding

b. Nausea and vomiting

c. Acid-base disturbance

d. Suppression of the cough reflex

e. Decreased tubular reabsorption of uric acid

(d) Answer is (d)- (a) & (b) are the major side effects of aspirin



19/49



19

(resulting from the inhibition of prostaglandin synthesis) for themajority of people, and one reason for the popularity of aspirinalternatives such as acetaminophen and ibuprofen, whichproduce these effects to a lesser extent. # 3 & 5 may also beseen following larger doses of aspirin. (d) is not seen withaspirin, but is a major therapeutic use of narcotic opiates suchas codeine. I guess they are hoping that you will get the effectsof codeine and aspirin mixed up, since the two are often

compared and contrasted as moderate pain relievers.

20. Which of the following is NOT true about acetaminophen?

a. Is a non-prescription drug

b. Is cross-allergenic with aspirin

c. Possesses both analgesic and antipyretic effects

d. May induce methemoglobinemia at high doses

e. May be the pharmacologically active form of acetophenetidin

(phenacetin)

(b) because it aint a salicylate, but the other statements are true

21. Which of the following is NOT true regarding acetaminophen?

a. It has antipyretic propertiesb. It may induce methemoglobinemia

c. It can be combined with codeine

d. It has anti-inflammatory properties

e. It is not cross-allergenic with aspirin

(d) reworded version of the preceding question, just asking whatyou know about acetaminophen. Nowadays, I think theywould also put something about liver damage in the

question, as below.

22. The most prominent acute toxic effect associated with

acetaminophen use is

a. Hemorrhage

b. Renal necrosis

c. Hepatic necrosis

d. Gastric ulceratione. Respiratory alkalosis

(c) Remember, acetaminophen (tylenol) is an aspirinalternative. Alternatives 1, 4, 5 are side effects of aspirin-typedrugs. The popularity of acetaminophen as an aspirin alternativeis because the incident of such effects with this drug is very low.However, because acetaminophen can undergobiotransformation to a toxic intermediate, hepatic and renalnecrosis have been reported, especially after very high doses.(c), hepatic necrosis is the most prominent, especially whencombined with alcohol consumption, since the alcohol inducesthe liver enzymes which make the hepatotoxic metabolites ofacetaminophen

23. Which of the following anti-inflammatory agents does NOT act

primarily by inhibiting the activity of cyclooxygenase?

a. Ibuprofen

b. Diflunisal

c. Prednisone

d. Indomethacin

e. Phenylbutazone

Answer is (c)- (a), 2, 4, and 5 are NSAIDS that reduceinflammation by reducing prostaglandin synthesis by blockingthe activity of cyclooxygenase. Prednisone is a corticosteroid.

Corticosteroids are potent nonspecific inhibitors of theinflammatory process, acting at a variety of point throughout theinflammatory process. Although they do reduce prostaglandinproduction as well, they do this by a mechanism other thenblocking cyclooxygenase, probably by inhibiting the release ofthe fatty acid substrate for prostaglandin synthesis.

24. Which of the following is the most appropriate drug to use to lower

fever in a child under 12?a. Aspirin

b. Ibuprofen

c. Acetaminophen

d. Salicylate

e. Diflunisal

(c) acetaminophen is the best choice. Aspirin is contraindicated due tothe potential for causing Reyes syndrome. Ibuprofen is approved,but usually not the #1 choice. The others would be inappropriate aswell.

25. Which analgesic from the following list has the longest half-life?

a. Acetaminophen

b. Aspirin

c. Diflunisal (Dolobid)d. Ibuprofen

(c) Diflunisal can be taken twice a day, the others three-four times aday is required.

Analgesics - Morphine

1. One of the most frequently asked questions concerns mixed-

agonist-anatagonists (MAA) - they ask you to identify which drugs

out of a list of 5 is an MAA. The one they usually expect you to

know is pentazocine, but sometimes nalbuphine. Since these

drugs have proved to be not very popular with patients, they

have fallen out of use, so I would imagine that they dont ask

somany questions on these drugs anymore.

2. Additional drug identifications they always ask involve knowing thatnaloxone is an antagonist used to treat overdose, and that

methadone is used in detoxification of morphine addicts.

3. Some questions give you a list of pharmacological effects and ask

you to identify which is not an effect of morphine. Morphine

produces respiratory depression, euphoria, sedation, dysphoria,

analgesia, and constipation and urinary retention. The substitution

they often make is diarrhea for constipation, or perhaps diuresis for

urinary retention.

4. The last most frequently asked type of question regarding opiates

concerns overdose of toxicity. In overdose morphine causes coma,

miosis, and respiratory depression. Sometimes they ask the

mechanism of respiratory depression: loss of sensitivity of the

medullary respiratory center to carbon dioxide.

Frequently asked questions on morphine:

5. Occurrence of which of the following is LEAST characteristic of

narcotic ingestion?

a. Vomiting

b. Diarrhea

c. Urinary retention

d. Bronchiolar constriction

e. Increase in intracranial pressure



20/49

20

(b) Again, the key word is least. Narcotics, in the form ofparegoric (tincture of opium), and Lomotil (loperamide) are overthe counter oral preparations for the treatment of diarrhea.Opiates act on receptors in the gut to produce constipation.Thus (b) is obviously wrong. All of the other answers are sideeffects of opiate administration.

6. Therapeutic doses of morphine administered intramuscularly may

produce

a. Constipation

b. Euphoria

c. Dysphoria

d. Mental clouding

e. Decreased response to pain

i. (a) and (b) only


iii. (a), (d) and (e)


v. All of the above

(v) memorize

8. Which of the following are pharmacologic effects of morphine?

a. Respiratory depression

b. Euphoria

c. Sedation

d. Constipation

e. Dysphoria

i. (a), (b) and (c)


iii. (a) and (e)


v. All of the above

(v) same question as above,, just reworded

7. Which of the following drugs acts to suppress the cough reflex?a. ASA

b. Codeine

c. Meperidine

d. Acetaminophen

e. Phenyibutazone

(b) the only drugs that do this are opioids, and codeine andmerperidine are the two opioids on the list. Of the two, codeineis much better at this than meperidine.

8. Morphine binds to which site to produce analgesia?

a. By binding to specific receptors in the CNS

b. By decreasing the influx of sodium

c. By decreasing the synthesis of prostaglandins

d. By decreasing nerve activatin at the site of injury

(a) They might reword the question in a way that asks you toremember that the specific receptors are the mu receptors.

9. Morphine causes vomiting by

a. A direct irritant action on the gastric mucosa

b. Stimulation of the nodose ganglion of the vagus nerve

c. Stimulation of the medullary chemoreceptor trigger zone

d. Direct stimulation of the gastrointestinal musculature

(c) is there such a thing as the nodose ganglion? Oh my god, I

just googled it and there really such a thing what a funnyname all these years I thought they just made this up. So itseems they want you to think that the emetic response tomorphine is locally activated,, but actually it is an effectproduced by morphine acting on the CTZ in the medulla.

10. The decrease in ventilation caused by morphine, meperidine and

some of the related opioids depends chiefly upona. Depression of cortical activity

b. Peripheral blockade of chemoreceptor impulses

c. An increase in carbon dioxide concentration in the blood

d. Blockade of afferent autonomic impulses from the lungs

e. Loss of sensitivity of the medullary respiratory center to carbon

dioxide

(e) memorization. Don't be fooled by (a)- these drugs aresedating, but this has nothing to do with the decrease inrespiratory rate.

11. Small doses of barbiturates and morphine depress respiration

primarily by

a. A parasympathominetic actionb. Inhibiting the Herine-Bueuer reflexc. Rendering the aortic chemoreceptor system insensitive to O2

d. Rendering the respiratory centerin the brain stem less sensitive

to changes in CO2

e. A specific effect at myoneural junctions of phrenic and

intercostal nerves

(d) I told you this in my lecture on morphine-if you miss thisyou'll hurt my feelings.

12. Which of the following are pathognomonic symptoms of narcotic

overdose?

a. Miosis, coma and depressed respiration

b. Mydriasis, coma and smooth muscle spasms

c. Mydriasis, coma and depressed respirationd. Miosis, convulsions and depressed respiration

e. Mydriasis, convulsions and depressed respiration

(a) pinpoint pupils (miosis) and respiratory depression arehallmark opioid overdose effects, so the only distractor is comaor convulsions. If you cant breathe too well, I guess you mightgo into a coma!

13. The cause of death with opioid intoxication is

a. Oxygen apnea

b. Cardiac arrest

c. Terminal convulsions

d. Circulatory collapse

e. Respiratory depression

(e) - again, a memorization question. What happens is thatopioids decrease the response of respiratory centers in thebrainstem to the carbon dioxide tension of the blood, and alsodepresses pontine and medullary centers regulating respiratoryfrequency. Opioids do not cause oxygen apnea, ((a)), they canbe convulsive, but not terminally so ((c)), they are stabilizing onthe heart and some are actually used in open-heart surgery((b)), and they do not cause circulatory collapse ((d)).



21/49



21

14. Which of the following is an opioid that has both agonistic and

antagonistic activities?

a. Codeine

b. Methadone

c. Naloxone

d. Meperidine

e. Pentazocine

(e) This is an example of the type of question where the drugclass is given. You are asked to not only identify a drug from thelist as being from this class, but additionally that it has theproperties that are given in the question that distinguish it fromthe other drugs of the class that are listed as alternatives. In thisexample, there is only one drug which meets this criterion. Allare drugs which act via opiate receptors, but 3 are agonists ((a),(b), (d)), 1 is an antagonist only ((c)). (e) pentazocine is the onlydrug which has both types of action, and is the one drug left bythe process of elimination.

15. A heroin-dependent patient should NOT be given nalbuphine (Nubain

) for pain because

a. It has no analgesic properties

b. It may produce respiratory depressionc. As a mixed agonist-antagonist, it can elicit withdrawal

symptoms

d. The high abuse potential of nalbuphine may add to the patient's

problems

(c) see above

16. A patient while not currently taking drugs has a history (6 months

ago) of narcotic dependency. Which of the following analgesics

should be avoided in this patient?

a. Aspirin

b. Pentazcine

c. propoxyphene

d. Indomethacin

e. Acetaminophen

f. None of the above

(b) see above

17. Which of the following statements does NOT characterize

pentazocine?

a. It is equianalgesic with codeine

b. It is a partial opioid antagonist

c. Its abuse potential is less than that of heroin

d. It may induce dysphoria and mental aberrations

e. It is effective only on parenteral administration

(e) lot of memorization required here for a drug that isnt

used that much. I guess it was big news when thesequestions were written many years ago and they seemed

hopeful, since statement (c) was true and wastherapeutically an advantage, but it soon became apparent

that (d) was also true

18. The antagonist of choice in the treatment of opioid overdosage is

a. Naloxone

b. Nalorphine

c. Pentazocine

d. Levallorphan

e. Propoxyphene

(a) nalorphine and pentazocine are mixed agonist-antagonists,levallorphan is an opioid agonist, as is propoxyphene

19. Which of the following is a complete antagonist of the opioid receptor

and the agent of choice in the treatment of narcotic overdose?

a. Naloxone

b. Nalorphine

c. Cyclazocined. Levallorphan


(a) reworded version of the preceding question

20. Methadone is used in detoxification (drug withdrawal) of patients

physically dependent on morphine because methadone

a. Precipitates withdrawal reactions

b. Antagonizes the depressant actions of morphine

c. Will not in itself produce physical dependence

d. Withdrawal reactions are less intense and stressful than those o

morphine

(d) This is an example of the kind of question that requires that

you have memorized a fact about a particular drug, in this casethe fact is (d). Methadone you will remember is not anantagonist like naloxone- it is a full agonist with analgesicproperties, just like morphine. When taken orally it is noteuphoric in addicts, but acts just like morphine to producetolerance and physical dependence. Withdrawal is less severethan with morphine because methadone has a much longer halflife. Facts 1, 2, and 3 would be met by an antagonist such asnaloxone, or perhaps even a mixed agonist-antagonist such aspentazocine.

21. Which of the following drugs is currently widely used in treating

opioid-dependent individuals?

a. Codeine

b. Methadone

c. Alphaprodine

d. Pentazocinee. Meperidine

(b) shortened version of the above question

22. Meperidine (Demerol) is

a. An antidepressant

b. An opioid analgesic

c. A sedative

d. A long-acting local anesthetic

e. An antipsychotic

(b)

Autonomics:

Cholinergics

1. Drug identification type questions that involve mechanism of action.

You need to know the following types of facts:

a. atropine, scopolamine, propantheline are competitive muscarinic

receptor blockers which sometimes are used to control salivary

secretions. An additional fact that often gets asked about

atropine has to do with the fact that it blocks vagal reflexive



22/49

22

control of heart rate, resulting in tachycardia.

b. physostigmine and neostigmine are reversible anticholinesterases

that differ in that physostigmine acts both centrally and

peripherally, neostigmine only peripherally, but neostigmine also

has some direct ACh like activity at the neuromuscular junction,

in addition to prolonging the activity of endogenous ACh. They

sometimes see use in treating xerostomia.

c. pilocarpine, methacholine, etc. are direct acting cholinergic

agonists. May be used for xerostomia.d. organophosphates and insecticides irreversibly inhibit